Coupling device



Oct; 2, l945. l E. M. Ml-:LHINNY` oUPLINc- DEvIc-E.

Filed sept. 6, 1943 l ww@ m n mw MNM MN NR www NW mm,

Patented Oct. 2, 1945 UNITED STATES PATENTy OFFICE i assaossff f A' i COUPLING DEVICE Eric M. McElhinney, Dysart,` Iowa Application September 6, 1943, Serial No. `501,435

` iclaims. (ci. 28o-33.15)

This invention relates generally to coupling devices and in particular to a couplingdevice for connecting atrailer unitwith a tractorfunit.

An object of this invention' is to provide an improved coupling.' f l Another object of this inventionis to provide a'coupling'device for atractor unit and a trailer unit in which a hitch portion onV one of such units is positively but'releasablylocked with a hooked portion on the other of the units. y

"'A further'object of this invention is toprovide a coupling device in which "a'pcsitive'locking'of a hitch portion in a hook "and the release of the hitch from' the hook is accomplished entirely by a reversible movement of an interconnected latch member and locking member; Y

Yet another object of this invention is`to pro-A vide a. coupling device in which a latchmember and a locking member are relatively assembled and constructed for concurrent movement incne direction to a locking position, but movable from such locking position only after thej locking niember is initially moved in an opposite direction.

A feature of this invention is found in ther provision of a coupling device having a body mem` ber with a hook at one end, in which a latch for closing the hook and a member for locking the' latch in a hook-closing" position are `pivotally supported in an offset relation adjacent the'other' end of the body member. The latch and the lock on pivotal'movement in the same direction to hook-closing and latch-locking positions, respec`` tively, are concurrently relatively movable 'longi-r tudinally and constructed With coacting' engageable portions which at such positions lock' the latch against pivotal movement in a'` reverse 'direction.

Another feature of this invention is found in the provision of a coupling device-in which a` tension means is relatively assembled with a pivoted hook-closing latch and a pivoted member vfor lockingtheflatch in a hook-closing position Fig. 4 is illustrated similarly toFig. 2 showing parts of ythe coupling device in yet another changed position;

`Fig.` 5 is a sectional view taken on the line 5--5 of Fig. 2 showing the coupling connected with a transversely extended draw bar;` and Fig. 6 is illustratedsimilarly to Fig. 5 showing the coupling connected with a longitudinally extended draw bar;

With reference to the drawing the coupling of this 'invention is shown in Figs. 1 and 2 as including a at body member I0 having a transversely extended hook II at one end, open as' indicated at I2 to one side I3 of the body member Ill. The

free end I4 of the hook II is substantially normal to the plane of the body member I0 and projects upwardly, as viewed in Fig.2, above the level of the sideI3. The member I0, opposite the side I3, carries a 'xed plate member I'I which cooperates with a removable plate I8 for connecting the body member I0` with a draw bar on a tractor unit (not shown), as will be later explained. Y 1 i The hook I I is capable of receiving through its opening I2 ahitch, indicated at 34, carried on a trailer unit (not shown) d which hitch is positively but releasably locked in the hook II by means now to be described.

. VThe body member I0 at its end 36` opposite the hookV II,` is provided witha supporting unit extended upwardly from the body member side I3 and comprised of a pair of transversely spaced plates 31 welded or otherwise suitably secured to the body member I0 (Figs. 1 and 2). Adjacent thebody member I0 and inwardly from its end 36 is a pivot pin 38 extended between th'eplates 3l. A pivot; `pin 39 is also extended; between the plates 31 ata position above theY pivot pin 38,as viewed in Fig. 2, and adjacent the body member end 3B so as to be oiset both vertically and horizontally vrelative to the pin 38.

such that the 4tension meansis capable of'alter- .n

nately maintaining lthe pivoted member in a latch-locking position and of holding the pivoted cent the freeend 43 of the latch. The latch is of member -andlatch Aaway' from a hook-closing f position. v

Further objects, features and advantages l of this invention will become apparent from the fol-` lowing description when taken in connection with the accompanying drawing in which:

Fig. 1 -is a plan viewof thecoupling of A'this parts thereof in changed position; I

"showing` a length `such that it is pivotally movable in a clockwise direction, as viewed in Fig. 2, toa limiting position against the side I3 of the body member I0 and in substantially parallel alignment with the side.V I3. In this limiting position the 55 Fig. 2is anelevationalY view of the coupling latch 4I. isvin a closing position with the hook opening I2 with its end 43 located inwardly or tothe left of the hook end I4. as also viewed in Figgz. i

A bar 44 vof straight form forlocking the latch 4lin a hook-closing positionis pivotally sup` ported at one end betweenthe plates 31 and on the pin 39.Y The bar 44 on pivotal movement in a clockwise direction, as seen in Fig, 2, is may.

its free end 41 engageable with the side 48 of the upstanding lug 42 on the latch 4I;

with inenteniaiigasd1ocksgzbaru in their relativesuperposed positions on the 'body mem-- ber side I3 (Fig. 2) and with the latch intermediate the body member I and the bar 44, anyv force applied at the free end 43 of the latch-tend-A ing to move the latch in a counter-clockwise direction away from a hook-closing position is y transmitted through the latch lug 42 lto the locking bar 44 and 1ongitudinally'of the locking bar tol its pivotal support 39. This force is thus directed through the axial center of the pivoted support 3.9"so that there is no moment' arm of thel b`ar`44 about'lts pivotal support orr axis'. 3,95 As'a result a toggle effect is produced by whchthe latch4 is positively locked ina hook-closing position by the bar 44. 'v I In order to 'release tlielatch 4IY from a hookcl'osing' positionv the locking 'barl '44' Vis initially movecl'in a counterclockwise directionfuntl its free end 41 is out of an engagingf position with the upstanding lug42l'on the latch, at Yvvhichgtime the' latch 4I isv freely movable away froi a)v hookclosing position; j 1

VFrom `a consideration of `Figs. 2` and 4 it' is seenthat the latch 4I andthe lockngbar 44 are pivotally movable "thro'ugh different arcuate paths.` To moverthe latch -4'I`i'n a'predetermined relation with theV locking bar 44 and in'response to thelmanipulation vof the 'bar' 44 toward land away from a latch-locking position concurrently witha corresponding movement' of the latch toward and away fromV a hook-closing' position, the latch andbarare connected together by'a lost motion mechanism including a pair of links or armse. The links 49 are pivotally connected at one of'their corresponding ends to `opposite sides ofl the latch Nonr yay pin 5I` extended transversely through the latch. `E`ach one of the opposite corresponding endsof" the links is formed with-a longitudinally extended slot 52 for slidably receiving a pin 513 carriedtransversely of the loc-king bar 44. j Thus on lifting the locking bar 44 from .its latcli-locking position -shown'irr Fig'. 2', the bar 44 is initially pivotally moved ina counterclockwise direction-independently ol' the latch 4I until. the pin. 53 engages the ends 54 of the slots 52 asI shown. inV Figi. 3. l Vlhen this engagement takes place the free end 410i the locking bar 44 is out of an. engaging-,position-with the upstanding lug 42 on the latch4l. Ona further lifting movement of the bar 44 the latch 43 is freely "positions, respectively, and for the lifting of the bar 44 out of a latch-locking position prior to 'Atl'ielm'ovement of the latch from a hook-closing position, all in response to the manipulation of the locking bar in reverse directions. This vmanipulation of the locking bar is facilitated by a handle portion 5S carried at its top, as shown in movable in a counter-clockwise direction together with the bar 44 by virtue of the position of the bar .in a spacedrelati'on relative to the latch 4I as is clearly shownin Fig..3, As aresult after the lostY motion, istaken up bythe links 49 the bar 44 and the latch 4I are Amovable together to their hook-openingpositionshown in Fig.. 4.

On z.a reverse movement of the latch and ybar to a hook-closing position the: latch and bar are initially, moved together"v from. .their positions shown in Fig. 4 toward their positions shown in. Fig. 2, the lockingbar duri-ng thisinitial moverilentbeing slidably engageable with the latch lock 42', and with the latch 4I later dropping Vaway from the locking bar 44 substantially to its positionshown in Fig. 31 lt is seen, therefore, ,thatA the latch 4I`fis movable to ya hook-.closing position" priorto the vr'nove'n'ientof the-bar 44130- a' latch'locking position( This movement of the latch and bar to'their positions shown in Fig. 2

rig. 2.

'I'he locking bar 44 is yieldably held in a latchlocking position with the lug '421er a pair' of tension springs 5T one oi'which islocated to each side of the supporting plates 31. Each spring is connected at one end to the pin 53 in the bar 44 and at its opposite end to a pin 58 located below the pivot pin 39 yand extended through the plates 31. seen in Fig. 2 the pressure ofthe springs, when the bar 44 is n a latch-locking position, is applied to the right of the pivotal support 3 9' so that the free end 41 of the locking bar 44 is continuously urged into engagement' with the latch lug 42. It is apparent, therefore, that the springs 51' are entirely free of any forces tending toA move the latch away from a hook-opening position, since such forces are applied only through the locking bar to its pivotal support 39. On movement of the lock and latch t0 their relativepositions shown in Fig. 4 the longitudinal axes of the springs 5T are moved through the pivotal support 39 so that the force of the springs is applied to the left of the pivotal support as viewed in Fig. 4, to yieldabl'y hold the latch and lockaway from a hook-closing position. The springs' thus function to alternately yieldably hold the bar 44 in a latch-locking position and the bar 44 and latch 4Iv out of a latch-locking position and a hookclosing position, respectively.

The plates |=1 and I8, previously mentioned for connecting the body member I0 With a tractor unit, are of a substantially square shape Yhaving corresponding holesin each of Vtlie corners thereof for receiving connecting bolts I9.`V Each plate I1 and I8 is further provided with a series of holes 2|' and 22,v respectively, spaced longitudinally of the coupling and extended centrally of a corre-l sponding plate I1 and I8 for receiving connecting plugs 23. The 'plugs 23 are of a reduced diameter at one end tot into the holes 22 of the plate I8 and are retained between the plates, while spacing such plates laterally apart from each other, by engagement of a shoulder 24 with the plate I8.

' Draw bars for tractor units are generally of two types, namelyextended either transversely or longitudinally of the tractor unit and in turn of the coupling. When a transverse draw bar 26 (Figs. 2. and 5) is used one 0i the longitudinally spaced holes 21 inthe bar is aligned with the hole indicated as 21a, which is located substantially centrally of. the plate I1 and a plug 23 is extended through the. bar and into central hole 2 la. The plate I8 is then placed adjacent the plate I1 with the reduced end of the plug 23 inserted within the -central hole 22a in the plate` I8, after which the bolts I9 are tightened to hold the plate I8 in a spaced relation with the plate I1 so that the bar 216 is loosely pivoted. on the plug 23 between the; p ates.

In the use of a longitudinally extended draw bar 29 (Fig. 6) a pair of openings 3| and 32 in the bar are aligned with a pair of corresponding holes 2| and 22 in the plates I1 and |8, respectively, the corresponding series of holes 2| and 22 being unequally spaced so that the coupling may be readily connected to longitudinally extended bars having the holes therein spaced varying distances apart. A plug 23 is then extended through each hole 3| and 32 and positioned within and between the plates I1 and I8, the same in all respects as was explained above for the transverse bar in Figs. 2 and 5.

From a consideration of the above description it is seen that the invention provides a coupler device which is of a simple and rugged construction, comprised of a minimum number of parts and readily adapted to be applied to either longitudinally or transversely extended draw bars. A locking action of a hitch portion in a hook of the coupler is accomplished entirely by the relative construction of a latch and bar and their relative pivotal support in an oiset relation such that they are movable longitudinally relative to each otherduring their pivotal movement in diierent arcuate paths to hook-opening and closing positions. Further any forces tending to release the latch from a hook-closing position are entirely counteracted by virtue of the toggle action of the bar 44 and the engagement of coacting portions on the locking bar and the hook-closing latch.

Although the invention has been described with respect to a preferred embodiment thereof it is to be understood'that it is not to be so limited since modiiications can be made therein which are within the full intended scope of this invention as defined by the appended claims.

I claim:

1. A coupling device including a body member having a hook portion adjacent one end open to one side of said body member adapted to receive a hitch portion therein, means for releasably locking said hitch portion in said hook portion including a pivoted latch, a pivoted locking member, means pivotally supporting said locking member and latch in an offset relation on said body member to provide for a longitudinal movement therebetween concurrently with thleir pivotal movement in one direction to a position at which said latch is adjacent the one side of said body member and in a hook-closing position, coacting portions on said latch and locking member engageable in said position to lock said latch against pivotal movement in an opposite direction out of said hook-closing position, tension means connected with said locking member and body member for holding said locking member in a latch-locking position, and lost motion means connecting said latch and locking member so that on pivotal movement of the locking member in said opposite direction said locking member is initially moved out of a latch-locking position to provide for a later pivotal movement of said latch from a hook-closing position, with the line of pressure application of said tension means being movable through the pivotal support of said locking member, on pivotal movement of the locking member in said opposite direction, to re- 2. A coupling device including a body member having a hook portion adjacent one end open to one side of said body member and adapted to receive a hitch portion therein, a supporting member adjacent the other end of said body member and projected outwardly from said one side thereof, a pivoted latch, iirst axis means pivoting one end Vof said latch on said supporting member', a pivoted lockingmember, second axis means pivoting one end of said locking member on said supporting member, Said latch and locking member being pivotally movable in one direction to positions at which said latch is in a hookclosing position substantially parallel with said one'side of the body member, and said locking member is superposed on said latch in a substantially parallel relation with said latch, and a portion on said latch engageble with the free end `of said locking member, at said moved positions,

to lock said latch member against pivotal movement is an opposite direction away from a hookclosing position.

3. A coupling device including a body member having a hook portion at one end open to one side of said body member and adapted to receive a hitch portion therein, with the free end of said hook projected outwardly from the one side of said body member, a supporting member at the other end of s`aid body member extended outwardly from said one side, a latch member pivoted at one end on said supporting member ad'- jacent said one side and pivotally movable to a position substantially parallel to said one side and with the free end thereof extended across said hook opening to a,` position adjacent said hook free end, a locking member pivoted at one end on said supporting member at a position outwardly from the pivoted end of said latch for pivotal movement thereof to a position substantially parallel with and superposed on said latch member in a hook-closing position, and a projection on said latch member engageable With the free end of said locking member to retain said latch member against movement away from a hook-closing position.

4. A coupling device including a body member having a hook portion at one end open to one side thereof, with the free end ofsaid hook projected outwardly from said one side and said hook adaptedto receive a hitch portion therein below the level of said one side, an upright supporting member on said one side adjacent the other end of said body member, a latch member of straight form pivoted at one end on said supporting member and pivotally movable in one direction to a hook closing position against said one side and with the free end thereof extended across said hook opening adjacent to said hook free end, a, locking member of straight form pivoted on said supporting member and pivotally movable in said one direction, when said latch is in a hook-closing position, to a position substantially parallel with said latch, and a projection on said latch engageable with the free end of said locking member, at said moved positions of the latch member and locking member, to lock said latch member against pivotal movement in an opposite direction away from a hook-closing position.

ERIC M. MCELHINNEY. 

